Lipo slightly puffy

Advice needed. I've had these batteries (2x Multistar 16s 12c 16000mah) for about a year now and have only charged them nine times. 

A few weeks ago, I inadvertently plugged in the balance connector of one battery incorrectly, which created a spark and melted the leads. 

After about a week sitting in my lipo bunker, that battery puffed a little. It still feels solid (no gas that I can tell). I'm not sure if it's shot or still ok to charge. It's the one on the right. What do you think I should do? Is it still ok? Thanks in advance.
https://flic.kr/p/2hCwJ7y
https://flic.kr/p/2hCwJ7D
https://flic.kr/p/2hCtR2i
https://flic.kr/p/2hCxFVi
https://flic.kr/p/2hCwJ8a

It will most likely charge ok but use a low charge rate and monitor it for heat, certainly don't leave it to is own devices during charging and only outside. The other issue is puffed cells will have a higher IR which means the cell will sag and beat the other cells to lvc quicker, capacity/range will suffer.

Ok, thanks for the reply. I always balance charge them at 1c. Very dry outside, so I charge them in an ammo can in my fireplace. Sucks the batts will suffer, but at least I can still ride my scooter awhile until I figure out and save up for another way to power it. Maybe build my own battery with 18650 cells or go lifepo4. Beau coup bucks!

By a year old, a slight puff is kind of normal for the grade of lipos I have been using. The pack should be fine once you repair the leads. If it got real bad, you might have to strip off an end cell if the tab vaporized.

One nice thing about the pouch cells, when you do screw up, it usually will vaporize a lead or a tab, vs bloating a can cell.

by slight puff, I mean the pack is not rock hard anymore, but There is a noticeable degree of the pouch inflating. By the time its feeling a real soft, its nearing the end of its lifespan, in terms of capacity. It could go years more if discharged at 1c, for half capacity.

Puffed ruined, is always obvious. that looks like you inflated a rubber glove, often it bursts, or melted the shrink cover.

That's encouraging news! Can you explain "vaporizing a tab?" Not sure what that means.

Once I replace the balance connector, I' check the cells. If all are ok, I'll put both batts in storage mode, then charge them up.

So just an update: was finally able to replace the jst plug on the "puffy" lipo and plugged it into my balance charger to put into storage mode. As you can see via the link, all cells seem fine. Here's hoping the puffiness doesn't get worse and I can get more life out of these batteries.

Wouldn't mind building my own out of 18650s, but not sure how to balance charge them using my current equipment instead of a bms.
https://flic.kr/p/2hEmY9f

SpaceKaseJase said:

Wouldn't mind building my own out of 18650s, but not sure how to balance charge them using my current equipment instead of a bms.
https://flic.kr/p/2hEmY9f

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You just wire balance plugs (like the ones you have) to the parallel cell groups. But I don't understand why you wouldn't want to use a balancing BMS instead. It's not hard to install, and it's easier to live with.

I understand what you're saying, however, I spent a lot of money on my power source and balance charger, so I want to get more use out of it if possible.

As for the balance plug wiring, I did some research and determined I would need 13s, 5p lion cells for the same size battery as my two lipos (12s, 16000 mah). Not sure how to wire 13s when my charger has 6s limit. I'm probably incorrect about how these cells work. Just need to do more research.

I suppose my worst case scenario would be to get a bms. It's not out of the question. Thanks for the reply.

A momentary short like that isn't going to have much of an effect on the cells themselves, it's not going to produce a high enough current for a long enough time to overheat anything internal.

The actual damage is pretty much what you saw, melted (vaporized) connectors and wires.

The fact that the cells happened to slightly puff afterward is just coincidence, there's no way enough current can flow through a tiny balance lead to hurt a big LiPo cell like that. Not before the wire turns to vapor.

I appreciate your reply, as it puts me a bit at ease.

I suppose it's due to the age of the lipos themselves then. Got a good deal on them last October, but they're no longer in production. Alternative lipos are way more expensive, hence the possibility of making my own using 18650.

Going to try and charge them up today and ride my scooter while the weather is still nice.

Re vaporizing a tab. When you short a lipo pack on the big wire, typically the foil tab on one of the end cells vaporizes in a flash,, Usually, holding the wires, you also can get Kentucky fried fingers because there is some welding going on in the plug at the same time. KFF. Its possible to melt just the plug, but I have usually melted the tab on the first positive cell in the pack. Its unrepairable, that first cell is ruined, so your 6s pack just became a 5s, if you move the + wire to the next cell in.

What you did I think, was connected up in a way that created a short on a balance wire, and melted a balance wire, or a plug. In that case, the wire melts before the tab on the pack. In a short, the place with the most resistance will melt, usually in a flash, vaporizing it. It may be a plug, a wire, or a tab on the foil pouch. You have to take apart a lipo pack to see the tabs.

The slight puffing is just normal aging, but they still have at least a year of good use in them, typically.

That's what I figured, especially since all 6 cells show normal voltage. I replaced the female jst-xh plug on the paraboard and the balance plug on the lipo. Everything seems fine. Put both packs into storage mode and was going to charge them up to take a ride this past weekend, but didn't get around to it. Maybe next weekend. Puffiness due to aging seems to be the culprit, though the timing of the balance plug short seemed too coincidental.

I have the same scooter you have (or had) and a 14s7p of 18650 size cells using a vruzend v2.1 kit fits perfectly with just enough space left for thin insulation. Its very snug but comes out easily and theres no room for bouncing around. I did remove the kickstand temporarily because of the idiotic bolt through design. I plan on brazing it to the same spot it was bolted on . There is no room for a bms , so you'd have to use balance plugs and your hobby charger, but you preferred that anyway. The one necessary mod is to make a non conductive durable floorpan . I cut a clipboard and sanded it to where it looks like it was made for it. A thin cutting board works well too.

That's a great idea! Was wondering if you might have a schematic on the wiring of your battery, esp the balance plug wires. What balance charger do you use including ps and paraboard? What type of motor are you using? I use a 48v 1500w brushless Boma inrunner. Can you also give me a ballpark as to the cost of your battery build? Too many question, I know. Thanks for the comment.

SpaceKaseJase said:

That's a great idea! Was wondering if you might have a schematic on the wiring of your battery, esp the balance plug wires. What balance charger do you use including ps and paraboard? What type of motor are you using? I use a 48v 1500w brushless Boma inrunner. Can you also give me a ballpark as to the cost of your battery build? Too many question, I know. Thanks for the comment.

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I'm using the stock "1000watt" brushed motor and dinky 35A controller that it came with. I have been hesitant to put much money into this thing until I feel confident that it won't start falling apart in the next 6 months. I've only had it since March , but I'm more optimistic now than I was at first. It does 30mph in stock motor, gearing , and controller , and that's fast enough on those little 11 in tires for me . As far as the wiring, I don't have a bms nor balance leads on it yet, due to the balance being very stable thus far. I charge using a meanwell led supply and monitor the voltage with a DMM . I'm using PF cells that I connected all 98 cells in parallel for 2 days prior to assembly to allow it to balance itself . Once that was done , I just check it once per week for balance and it has stayed within less than .01v of each other the whole way. As soon as it gets some age on it, I will get a hobby charger that will do 7s and remove the bus bars to split the pack evenly and charge each "half " to 4.2v on a balance cycle, reconnect the bus bars and go on my way. I would be shocked if I have to balance them more than once every couple months for quite a while. If you need a link to a website that sells balance leads cheap, I can dig it up. One thing I forgot to mention, is I drilled a 3/8 in hole in the space just above the controller and ran my controller wires up and outside so my battery leads could connect without having to run them inside the same compartment the controller is in. I just ran the battery leads under the plastic deck since there is about 4- 6mm of a gap due to the mounting "hinges" . I can stand on the area above the 14ga battery wires and it doesn't put any pressure on them. The battery takes up every bit of available space in the battery tray and there is no room at all for wiring terminals , at least safely. I use the 40amp anderson power poles because they're small and connect very easily while maintaining a solid connection. Very low resistance as well. This way I can add in an inline fuse, and any kind of meter I want to connect without doing a lot of bullcrap with wire routing. If this sounds like a cluster F### and confusing, I will take some pics to show you my setup. I took a chance and bought the cells from a company in California that resells end of life products . They were dated 2014 , but it seems I was very lucky that there were no bad cells and they all were completely free of any evidence of prior use. So , I have $225USD in 100 cells , $160 in Vruzend kits and just the cost of the HLG-480H-54A @ $125 . Once those cells wear out , I will only have to buy new cells , plug them in and go. The Vruzend kits can be a little irritating to assemble at first, but they're proving very reliable and super convenient . The beauty of having all those left over caps and hardware , is you can use a tension rod in almost every hole to keep the connections tight and secure. This wouldn't work as well on a bike, but it's a great match for these "Uberscoot" type scooters.

The one reason I went with the "Uberscoot" style frame was the fact that it was sturdy, had two disc brakes, and dual suspension. I've taken mine to 32 mph with no fear of it falling apart. My controller is a Kelly 55a continuous. Would appreciate a picture of your battery and scooter setup for reference. I like the 3/8 hole idea. Is it for convenience?

I won't have the money to replace the batteries until around June, so I hope my current lipos hold up. At least I have time to consider options. If you could provide that battery link, it would be appreciated.

Btw, how did you know about the type of scooter I have? Was it mentioned in another post, or have you visited my modifiedelectricscooters.com blog? The site is now dead. Just curious.

Without bms most poeple build a big parallel pack and bulk charge and check with the sense wires with and balance thru them

SpaceKaseJase said:

The one reason I went with the "Uberscoot" style frame was the fact that it was sturdy, had two disc brakes, and dual suspension. I've taken mine to 32 mph with no fear of it falling apart. My controller is a Kelly 55a continuous. Would appreciate a picture of your battery and scooter setup for reference. I like the 3/8 hole idea. Is it for convenience?

I won't have the money to replace the batteries until around June, so I hope my current lipos hold up. At least I have time to consider options. If you could provide that battery link, it would be appreciated.

Btw, how did you know about the type of scooter I have? Was it mentioned in another post, or have you visited my modifiedelectricscooters.com blog? The site is now dead. Just curious.

Click to expand...

The reason for the drilling was to bring the B+ and - out the top so I could quickly and easily connect the battery without having to deal with the tight mess of wires inside the controller "compartment" . With the Anderson plugs, it would have been a pain to connect it in there with such limited space and there really was no available space in the battery compartment at all. Anywhere i tried to put the connectors would have been a short waiting to happen. I made a grommet out of shrink tubing and hot glue where the controller wires exit. Also important to file the sharp edges ( Duh , I know. Better to mention it than not) . I bought mine for the same reasons you did. My main concerns were the calipers and headset , but they're doing fine so far. Im going to put real shocks on it soon and probably calipers and rotors .

The link to your battery pics are on Flicker , so your scooter was on there . I was curious how yours was set up . Totally dig the color scheme and the meter in the padding. That was a good idea. I lost the link to the website for the balance leads , but you can get them off Amazon pretty cheap . less than $10 for 10 of them I think.

https://www.amazon.com/CynKen-Terminal-Balance-Charger-Connector/dp/B06W2L5F2H/ref=sr_1_3?gclid=Cj0KCQiA-4nuBRCnARIsAHwyuPp-JR0zNFthmfQriDW7aSdoikIzxSlrqU0O7Og9-YXVOHXx88tGwAgaAuOtEALw_wcB&hvadid=341292103177&hvdev=c&hvlocphy=9032862&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=11844716837870470236&hvtargid=kwd-301582812120&hydadcr=24659_9648993&keywords=7s+balance+leads&qid=1573082191&sr=8-3

* Edit* I just realized that the Icharger 206b will only balance 6s . You could always split the pack into 2 groups of 6s and charge the remaining 2 groups separately. Either way , if your charger is fairly accurate , they should be very close.

Here is another supplier for leads. They have 2s - 6s leads very reasonably priced. https://www.racedayquads.com/products/2s-balance-lead-jst-xh-10pcs-2s1p-balance-connector-male-female-plug

The idea is to lay all of your parallel bus bars down first and do series connections last , so that you can easily remove the series bus bar right off the top to isolate your sections . Instead of soldering a bunch of heavy leads to charge these sections , the best bet would be to make a removable lead with ring terminals on the battery end. That way you can just remove a couple nuts and stick it on the next section to charge. All this probably seems a little bit of a pain , but considering what can happen if a bms fails , I don't have a problem taking a little extra time once a month to do it this way. A good bms is worth its weight in gold, but it also costs it's weight in gold. The cheap ones are straight up roulette .

https://flic.kr/p/2hGjknG
https://flic.kr/p/2hGfPYo
https://flic.kr/p/2hGjky3

Dak77 said:

A good bms is worth its weight in gold, but it also costs it's weight in gold. The cheap ones are straight up roulette .

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I'll take the cheapest BMS a hundred times out of a hundred compared to no BMS (which is for me the plausible alternative). It's no harder to figure out whether it's working correctly than it is to do monitoring and balancing manually, and you don't have to do it nearly as often.

Cheap ones have a habit of being black boxes, can't handle the current lipo can deliver, and can murder the battery themselves..

I don't use RC Lipo anymore as i've had my high power fun, but i'd still rather not have one with my 18650 packs.. if i'd build them to be properly matched anyway. A well matched pack only requires balancing once a year and you can do that in sections with an RC charger

neptronix said:

Cheap ones have a habit of being black boxes, can't handle the current lipo can deliver, and can murder the battery themselves..

Click to expand...

My method is to have one battery, so it gets regular exercise. The more often it's charged, the more it stays balanced. I don't even have to know the details of what the BMS is doing. Every once in a while, I use a multimeter to probe the cell voltages. I find them to be matched, and I let it go until the next time. If for some reason I left the battery idle for a long period, I would disconnect the BMS.

Compared to balance charging or manual cell balancing, this seems a lot easier.

Balmorhea said:

neptronix said:

Cheap ones have a habit of being black boxes, can't handle the current lipo can deliver, and can murder the battery themselves..

Click to expand...

My method is to have one battery, so it gets regular exercise. The more often it's charged, the more it stays balanced. I don't even have to know the details of what the BMS is doing. Every once in a while, I use a multimeter to probe the cell voltages. I find them to be matched, and I let it go until the next time. If for some reason I left the battery idle for a long period, I would disconnect the BMS.

Compared to balance charging or manual cell balancing, this seems a lot easier.

Click to expand...

You aren't wrong. My luck is such that I would get the 1 out of 500 units that drained 2 cells while the rest saturated .

Dak77 said:

SpaceKaseJase said:

The one reason I went with the "Uberscoot" style frame was the fact that it was sturdy, had two disc brakes, and dual suspension. I've taken mine to 32 mph with no fear of it falling apart. My controller is a Kelly 55a continuous. Would appreciate a picture of your battery and scooter setup for reference. I like the 3/8 hole idea. Is it for convenience?

I won't have the money to replace the batteries until around June, so I hope my current lipos hold up. At least I have time to consider options. If you could provide that battery link, it would be appreciated.

Btw, how did you know about the type of scooter I have? Was it mentioned in another post, or have you visited my modifiedelectricscooters.com blog? The site is now dead. Just curious.

Click to expand...

The reason for the drilling was to bring the B+ and - out the top so I could quickly and easily connect the battery without having to deal with the tight mess of wires inside the controller "compartment" . With the Anderson plugs, it would have been a pain to connect it in there with such limited space and there really was no available space in the battery compartment at all. Anywhere i tried to put the connectors would have been a short waiting to happen. I made a grommet out of shrink tubing and hot glue where the controller wires exit. Also important to file the sharp edges ( Duh , I know. Better to mention it than not) . I bought mine for the same reasons you did. My main concerns were the calipers and headset , but they're doing fine so far. Im going to put real shocks on it soon and probably calipers and rotors .

The link to your battery pics are on Flicker , so your scooter was on there . I was curious how yours was set up . Totally dig the color scheme and the meter in the padding. That was a good idea. I lost the link to the website for the balance leads , but you can get them off Amazon pretty cheap . less than $10 for 10 of them I think.

https://www.amazon.com/CynKen-Terminal-Balance-Charger-Connector/dp/B06W2L5F2H/ref=sr_1_3?gclid=Cj0KCQiA-4nuBRCnARIsAHwyuPp-JR0zNFthmfQriDW7aSdoikIzxSlrqU0O7Og9-YXVOHXx88tGwAgaAuOtEALw_wcB&hvadid=341292103177&hvdev=c&hvlocphy=9032862&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=11844716837870470236&hvtargid=kwd-301582812120&hydadcr=24659_9648993&keywords=7s+balance+leads&qid=1573082191&sr=8-3

* Edit* I just realized that the Icharger 206b will only balance 6s . You could always split the pack into 2 groups of 6s and charge the remaining 2 groups separately. Either way , if your charger is fairly accurate , they should be very close.

Here is another supplier for leads. They have 2s - 6s leads very reasonably priced. https://www.racedayquads.com/products/2s-balance-lead-jst-xh-10pcs-2s1p-balance-connector-male-female-plug

The idea is to lay all of your parallel bus bars down first and do series connections last , so that you can easily remove the series bus bar right off the top to isolate your sections . Instead of soldering a bunch of heavy leads to charge these sections , the best bet would be to make a removable lead with ring terminals on the battery end. That way you can just remove a couple nuts and stick it on the next section to charge. All this probably seems a little bit of a pain , but considering what can happen if a bms fails , I don't have a problem taking a little extra time once a month to do it this way. A good bms is worth its weight in gold, but it also costs it's weight in gold. The cheap ones are straight up roulette .

https://flic.kr/p/2hGjknG
https://flic.kr/p/2hGfPYo
https://flic.kr/p/2hGjky3

Click to expand...

Ok that makes a little more sense, now that I've seen your pics. Remove series bars in order to charge, then replace them when plugging into scooter. You weren't kidding when you said there was hardly any room in the chassis except for the battery. As you saw, all my wiring, lipo monitor, lipos, and fuse fit in my box with room to spare. I suppose my next question is why did you choose 18650 over lipos? Are they much safer/more efficient?

SpaceKaseJase said:

Dak77 said:

SpaceKaseJase said:

The one reason I went with the "Uberscoot" style frame was the fact that it was sturdy, had two disc brakes, and dual suspension. I've taken mine to 32 mph with no fear of it falling apart. My controller is a Kelly 55a continuous. Would appreciate a picture of your battery and scooter setup for reference. I like the 3/8 hole idea. Is it for convenience?

I won't have the money to replace the batteries until around June, so I hope my current lipos hold up. At least I have time to consider options. If you could provide that battery link, it would be appreciated.

Btw, how did you know about the type of scooter I have? Was it mentioned in another post, or have you visited my modifiedelectricscooters.com blog? The site is now dead. Just curious.

Click to expand...

The reason for the drilling was to bring the B+ and - out the top so I could quickly and easily connect the battery without having to deal with the tight mess of wires inside the controller "compartment" . With the Anderson plugs, it would have been a pain to connect it in there with such limited space and there really was no available space in the battery compartment at all. Anywhere i tried to put the connectors would have been a short waiting to happen. I made a grommet out of shrink tubing and hot glue where the controller wires exit. Also important to file the sharp edges ( Duh , I know. Better to mention it than not) . I bought mine for the same reasons you did. My main concerns were the calipers and headset , but they're doing fine so far. Im going to put real shocks on it soon and probably calipers and rotors .

The link to your battery pics are on Flicker , so your scooter was on there . I was curious how yours was set up . Totally dig the color scheme and the meter in the padding. That was a good idea. I lost the link to the website for the balance leads , but you can get them off Amazon pretty cheap . less than $10 for 10 of them I think.

https://www.amazon.com/CynKen-Terminal-Balance-Charger-Connector/dp/B06W2L5F2H/ref=sr_1_3?gclid=Cj0KCQiA-4nuBRCnARIsAHwyuPp-JR0zNFthmfQriDW7aSdoikIzxSlrqU0O7Og9-YXVOHXx88tGwAgaAuOtEALw_wcB&hvadid=341292103177&hvdev=c&hvlocphy=9032862&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=11844716837870470236&hvtargid=kwd-301582812120&hydadcr=24659_9648993&keywords=7s+balance+leads&qid=1573082191&sr=8-3

* Edit* I just realized that the Icharger 206b will only balance 6s . You could always split the pack into 2 groups of 6s and charge the remaining 2 groups separately. Either way , if your charger is fairly accurate , they should be very close.

Here is another supplier for leads. They have 2s - 6s leads very reasonably priced. https://www.racedayquads.com/products/2s-balance-lead-jst-xh-10pcs-2s1p-balance-connector-male-female-plug

The idea is to lay all of your parallel bus bars down first and do series connections last , so that you can easily remove the series bus bar right off the top to isolate your sections . Instead of soldering a bunch of heavy leads to charge these sections , the best bet would be to make a removable lead with ring terminals on the battery end. That way you can just remove a couple nuts and stick it on the next section to charge. All this probably seems a little bit of a pain , but considering what can happen if a bms fails , I don't have a problem taking a little extra time once a month to do it this way. A good bms is worth its weight in gold, but it also costs it's weight in gold. The cheap ones are straight up roulette .

https://flic.kr/p/2hGjknG
https://flic.kr/p/2hGfPYo
https://flic.kr/p/2hGjky3

Click to expand...

Ok that makes a little more sense, now that I've seen your pics. Remove series bars in order to charge, then replace them when plugging into scooter. You weren't kidding when you said there was hardly any room in the chassis except for the battery. As you saw, all my wiring, lipo monitor, lipos, and fuse fit in my box with room to spare. I suppose my next question is why did you choose 18650 over lipos? Are they much safer/more efficient?

Click to expand...

Mostly due to ignorance , in that I mean lack of knowledge. The only vendor for lipos I knew of in the US that weren't priced stupidly , was Hobby King and after reading countless posts on various forums about the defect rate of their lower priced bricks , I backed away. I may actually try some now that I have a dependable go to battery. 18650s more efficient? I doubt. That would probably be a better question for one of the more knowledgeable people here. There are several with extensive experience using pouch cells. One thing to consider , is you would definitely feel a drop in power going down to a 14s setup from a 16s. I went the route I did based on what I felt was going to be the most dependable ,convenient, and safe option that I could afford at the time. As far as the size , keep in mind that those clunky Vruzend caps take more room than typical cell holders. You could get some wiggle room with a well designed 14s pack in there . As far as removing the serial bars; that's only needed when balancing occassionally . You can bulk charge day to day without moving anything . You would obviously need a 52v charger or adjustable power supply for bulk charging . The Meanwell I use lists the specs as 45.9 to 56.7v , but mine will do 44.8 all the way to 58.9v . Not bad having that much flexibility and proven dependability for $125 .

I did not see anything that I consider "puffy" in the original post.

For years now (and this is NOT advice) I have run packs that look like they are going to burst. So much puffing that the heat shrink splits and it looks like a balloon.

My experience has been that these continue to work. . . but if you set them to the side for 6mo and come back... you are more likely to see a zero'ed out cell than with another pack that is not puffy.

-methods